Conductivity cells are a well recognized means for measuring the conductivity of electrolytes. Electrolytic conductance is the transport of electric charge under electric potential differences by particles of atomic or larger size. This phenomenon is distinguished from electronic or metallic conductance which is due to the movement of electrons. Electrolytic conductors may be solids, liquids or gases.
Conductance is usually measured as the specific conductance, .kappa., which is the reciprocal of the resistance of a cube of material, 1 cm in each direction, placed between electrodes 1 cm.sup.2, on opposite sides of the cube.
Conductances of solutions and solids are usually measured by the Kohlrausch method in which a Wheatstone bridge is employed. The conductance cell containing the electrolytic conductor between electrodes is placed is one arm of the bridge. By using an alternating current between the electrodes of the cell, the electrochemical reactions are reversed on the half cycle. When a small alternating current is used for input signal to the electrodes, practically all the electric charge passed during each half cycle is stored in electric double layer which acts as a capacitor.
However, traditional conductivity cells are often not effectively employed with solid electrolytes particularly solids produced in situ, e.g., by curing of a liquid with ultraviolet radiation or an electron beam, due to the difficulty in removing the solidified electrolyte from the conductivity cell.
Furthermore, traditional conductivity cells can not be effectively employed to measure transport properties of solid electrolytes such as transference number and diffusion coefficient. Each of these properties can only be effectively measured when the electrolyte is sectioned which sectioning is difficult, if not impossible, to accomplish with traditional cells.
Moreover, in such environments, it would be preferable if the cell, or at least the chamber containing the electrolyte, was disposable.